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Abstract Mono-DPTA-ethyleneglycol-Ga-deuteroporphyrin (MDEGD) was synthesized, by coordinating non-radioactive Ga in the porphyrin ring and connecting DTPA (diethylene-triamine-N,N,N,N,N,-pentaacetic acid) to its side chain. By labeling with 111In, chemicals for scintigraphy were developed. They were applied to Syrian golden hamsters with implanted pancreatic gland cancers and C57-black mice with Lewis lung cancer to enable tumor imaging and biodistribution examination. A comparative study was also conducted with [67Ga]citrate. In the resultant data, [111In]MDEGD showed larger tumor/lung, tumor/kidney and tumor/blood ratio with [67Ga]citrate. The affinity of [nIn]MDEGD in inflammatory tissue was much lower than that of 67Ga citrate. [111In]MDEGD lost its photosensitivity.  相似文献   
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The electric quadrupole interaction of55Mn nuclei was studied in the weakly ferromagnetic system MnSi using muon level-crossing resonance (LCR) technique. The temperature dependence of the electric field gradient (EFG) shows a critical behavior near the ferromagnetic transition temperature, indicating that the EFG due to the conduction electron is strongly correlated with the magnetic susceptibility in the itinerant electron magnetism. The temperature dependence of EFG is in reasonable agreement with the self-consistent renormalization theory developed by Moriya and coworkers.We gratefully acknowledge helpful discussion with Dr. N. Nishida. We also wish to thank Keith Hoyle and Curtis Ballard for technical support.  相似文献   
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4-Monodeuterated NAD(P)H model compounds (1,4,6,7-tetrahydro-1,6,11-trimethyl-5-oxo-5H-benzo[c]pyrido[2,3-e]az epin; 11Me-MMPAH) have been oxidized with a series of p-benzoquinone and its derivatives in the presence of Mg2+. The models have an axial chirality with respect to the orientation of carbonyl dipole, the dihedral angle of which is larger than 55 degrees out of the plane of dihydropyridine ring. Without Mg2+, the anti- (with respect to the carbonyl dipole) hydrogen is 3 to 32 times more reactive than the corresponding syn-hydrogen, whereas, when Mg2+ is present in the system, the selectivity is shifted toward the syn-preferency. Mg2+ plays the role of a Lewis acid catalyst to control the stereochemistry at the same time as it catalyzes the reaction.  相似文献   
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Polymer-supported crown ethers were prepared from chloromethylated or ω-bromoalkylated polystyrene resins and hydroxymethylbenzo-18-crown-6 and 15- or 18-membered monoazacrown ethers. Effects of the cavity size of crown ethers, the degree of crosslinking, the degree of ring substitution, particle size, spacer chains, and solvents on the activity of the polymer-supported crown ethers in the reaction of 1-chloro- or 1-bromo-octane with aqueous NaI or KI were investigated and mechanisms of the reaction were discussed in terms of mass transfer, intraparticle diffusion, and intrinsic reactivity.  相似文献   
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